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                                                                   Exhibit 10.20



                                 AMENDMENT NO. 2
                                       TO
                      AMENDED AND RESTATED CREDIT AGREEMENT
                                      WITH
                             VISKASE COMPANIES, INC.


     THIS AMENDMENT NO. 2 TO CREDIT AGREEMENT ("AMENDMENT") is dated as of
October 26, 1998, by and between VISKASE COMPANIES, INC., a Delaware corporation
formerly known as Envirodyne Industries, Inc. ("BORROWER") and BT COMMERCIAL
CORPORATION, a Delaware corporation, individually and as agent (in such
capacity, the "AGENT") for the "LENDERS" under and as defined in the Credit
Agreement referred to below. Capitalized terms used herein but not otherwise
defined herein shall have the respective meanings assigned to such terms in the
Credit Agreement.


                                   WITNESSETH:

     WHEREAS, Borrower, Agent and Lenders have entered into that certain Amended
and Restated Credit Agreement dated as of June 1, 1998, as amended (the "CREDIT
AGREEMENT"), pursuant to which Lenders have agreed to make certain loans and
other financial accommodations to or for the account of Borrower;

     WHEREAS, Borrower has requested that Agent and Lenders further amend the
Credit Agreement; and

     WHEREAS, Lenders and Agent have agreed to further amend the Credit
Agreement on the terms and subject to the conditions hereinafter set forth;

     NOW, THEREFORE, in consideration of the premises set forth above, the terms
and conditions contained herein, and other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, the respective parties
hereto hereby agree as follows:

     1.     AMENDMENT TO CREDIT AGREEMENT.  Effective as of the
date hereof, upon satisfaction of the conditions precedent set forth in SECTION
2 below, and in reliance upon the representations and warranties of Borrower set
forth herein, the Credit Agreement is hereby amended as follows:

          1.1 The definition of the term "Net Worth" set forth in SECTION 1.1 of
the Credit Agreement is hereby amended by inserting the following language
therein immediately prior to the period at the end thereof:
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     ; and provided, further, that (i) restructuring charges incurred during the
     quarter ended as of September 24, 1998 in an aggregate amount not to exceed
     $58,000,000 (and provided that not more than 25% of which were incurred in
     the form of cash expenses) and (ii) non-cash charges incurred during the
     fiscal quarter ended as of September 24, 1998 in an aggregate amount not to
     exceed $91,200,000 for the write-down of excess reorganization value of the
     Company's assets, in each case shall be added back to the calculation of
     Net Worth to the extent such charges would otherwise be deducted in
     calculating such Net Worth and notwithstanding any tax effect of such
     charges.

     2. CONDITIONS PRECEDENT. This Amendment shall become effective as of the
date hereof, upon satisfaction of each of the following conditions:

          (a) As of the date first above written (after giving effect to this
     Amendment) no Default or Event of Default shall have occurred and be
     continuing.

          (b) Agent shall have received two (2) copies of this Amendment duly
     executed by Borrower.

          (c) Agent shall have received evidence reasonably satisfactory to
     Agent that the Third Supplemental Indenture to the First Priority Notes
     Indenture substantially in the form of EXHIBIT A hereto shall have been
     executed and delivered by Borrower and prior to or concurrently with the
     effectiveness of this Amendment shall have become effective pursuant to the
     respective terms thereof.

     3.  REPRESENTATIONS, WARRANTIES AND COVENANTS.

          3.1 Borrower hereby represents and warrants to the Agent and each of
the Lenders that:

          (a) this Amendment, and the Credit Agreement as amended hereby,
     constitute legal, valid and binding obligations of Borrower and are
     enforceable against Borrower in accordance with their respective terms,
     except as may be limited by applicable bankruptcy, insolvency or similar
     laws relating to creditors' rights generally and by general principles of
     equity (regardless of whether enforcement is sought in equity or at law);

          (b) after giving effect to this Amendment, no Default or Event of
     Default has occurred and is continuing; and

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          (c) the execution and delivery by Borrower of this Amendment does not
     require the consent or approval of any Person, except such consents and
     approvals as shall have been obtained.

     4. REFERENCE TO AND EFFECT ON THE CREDIT AGREEMENT AND THE OTHER CREDIT
        DOCUMENTS.

          4.1 Upon the effectiveness of this Amendment, each reference in the
     Credit Agreement to "this Agreement", "hereunder", "hereof", "herein" or
     words of like import, and each reference in each of the other Credit
     Documents to the "Credit Agreement," shall in each case mean and be a
     reference to the Credit Agreement as amended hereby.

          4.2 Except as expressly set forth herein, (i) the execution and
     delivery of this Amendment shall in no way affect any right, power or
     remedy of Agent or any of the Lenders with respect to any Event of Default
     nor constitute a waiver of any provision of the Credit Agreement or any of
     the other Credit Documents and (ii) all terms and conditions of the Credit
     Agreement, the other Credit Documents and all other documents, instruments,
     amendments and agreements executed and/or delivered by the Borrower
     pursuant thereto or in connection therewith shall remain in full force and
     effect and are hereby ratified and confirmed in all respects. The execution
     and delivery of this Amendment by Agent and each of the Lenders shall in no
     way obligate Agent or any of the Lenders, at any time hereafter, to consent
     to any other amendment or modification of any term or provision of the
     Credit Agreement or any of the other Credit Documents, whether of a similar
     or different nature.

     5. GOVERNING LAW. The validity, interpretation and cement of this Amendment
and any dispute arising out of or in connection with this Amendment, whether
sounding in contract, tort, equity or otherwise, shall be governed by the
internal laws (as opposed to the conflicts of laws provisions) and decisions of
the State of Illinois.

     6. HEADINGS. Section headings in this Amendment are included herein for
convenience of reference only and shall not constitute a part of this Amendment
for any other purpose.

     7. COUNTERPARTS. This Amendment may be executed in any number of
counterparts and by the different parties hereto in separate counterparts, each
of which when so executed and delivered shall be an original, but all of which
shall together constitute one and the same instrument.

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     IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly executed and delivered by their proper and duly authorized officers as of
the date first set forth above.


                                      BORROWER:

                                      VISKASE COMPANIES, INC.


                                      By:
                                               ----------------------------
                                      Name:
                                               ----------------------------
                                      Title:
                                               ----------------------------

                                      AGENT:

                                      BT COMMERCIAL CORPORATION, as Agent


                                      By:
                                               ----------------------------
                                      Name:
                                               ----------------------------
                                      Title:
                                               ----------------------------
                                      LENDERS:

                                      BT COMMERCIAL CORPORATION, in its
                                        individual capacity


                                      By:
                                               ----------------------------
                                      Name:
                                               ----------------------------
                                      Title:
                                               ----------------------------

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                                    EXHIBIT A
                                       TO
                                 AMENDMENT NO. 2
                          DATED AS OF OCTOBER 26, 1998


               FORM OF AMENDMENT TO FIRST PRIORITY NOTES INDENTURE
               ---------------------------------------------------

                                    Attached